GRASS GIS manual: r.li.padcv

Note: A new GRASS GIS stable version has been released: GRASS GIS 7.4, available here.
Updated manual page: here

NAME

r.li.padcv - Calculates coefficient of variation of patch area on a raster map

KEYWORDS

raster, landscape structure analysis, patch index

SYNOPSIS

r.li.padcv

r.li.padcv --help

r.li.padcv input=name config=name output=name [--overwrite] [--help] [--verbose] [--quiet] [--ui]

Flags:

--overwrite: Allow output files to overwrite existing files
--help: Print usage summary
--verbose: Verbose module output
--quiet: Quiet module output
--ui: Force launching GUI dialog

Parameters:

input=name [required]: Name of input raster map
config=name [required]: Configuration file
output=name [required]: Name for output raster map

DESCRIPTION
NOTES
EXAMPLES
SEE ALSO
REFERENCES
AUTHORS

DESCRIPTION

r.li.padcv calculates the coefficient of variation of patch area sizes in hectares as:
r.li.padcv formula

with:

SD: standard deviation of patch area size
MPS: mean patch area size
ai: area of patch i
Npatch: number of patches

Do not use absolute path names for the config and output file/map parameters. If the "moving window" method was selected in g.gui.rlisetup, then the output will be a raster map, otherwise an ASCII file will be generated in the folder C:\Users\userxy\AppData\Roaming\GRASS7\r.li\output\ (MS-Windows) or $HOME/.grass7/r.li/output/ (GNU/Linux).

The result is NULL if the sample area contains only NULL values.

EXAMPLES

To calculate patch area distribution coefficient of variation index on map my_map, using my_conf configuration file (previously defined with g.gui.rlisetup) and saving results in my_out, run:

r.li.padcv input=my_map conf=my_conf output=my_out

Forest map (Spearfish sample dataset) example:

g.region raster=landcover.30m -p
r.mapcalc "forests = if(landcover.30m >= 41 && landcover.30m <= 43,1,null())"
r.li.padcv input=forests conf=movwindow7 out=forests_padcv_mov7
r.univar forests_padcv_mov7

Forest map (North Carolina sample dataset) example:

g.region raster=landclass96 -p
r.mapcalc "forests = if(landclass96 == 5, 1, null() )"
r.li.padcv input=forests conf=movwindow7 out=forests_padcv_mov7

# verify
r.univar forests_padcv_mov7
r.to.vect input=forests output=forests type=area
d.mon wx0
d.rast forests_padcv_mov7
d.vect forests type=boundary

REFERENCES

McGarigal, K., and B. J. Marks. 1995. FRAGSTATS: spatial pattern analysis program for quantifying landscape structure. USDA For. Serv. Gen. Tech. Rep. PNW-351. (PDF)

AUTHORS

Michael Shapiro - CERL (patch identification)
Markus Metz (statistics)

Last changed: $Date: 2014-12-19 13:55:37 -0800 (Fri, 19 Dec 2014) $

SOURCE CODE

Available at: r.li.padcv source code (history)